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Lumen Review: Why It's A Waste Of Money

Lumen Review: Why It's A Waste Of Money

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Read our Editorial Guidelines to learn more about what makes our site the premier resource for online health information.

Read our Editorial Guidelines to learn more about what makes our site the premier resource for online health information.

Lumen is a tech company with a bold claim: that they’ve manufactured a device that can help you “hack your metabolism” to increase fat loss, lose weight, and boost energy naturally.

In this article we’ll review some of the health claims made by Lumen in light of published medical research (or lack thereof), discuss whether metabolic flexibility is even real, and conclude with whether or not we recommend this device.

What Is Metabolic Flexibility? 

Lumen’s value proposition centers on a concept called metabolic flexibility, which refers to the body’s ability to shift between burning fat or carbs as a primary energy source.

Metabolic flexibility is a real term used in the medical community. A medical review published in the Cell Metabolism journal in 2017 analyzed metabolic flexibility in health and disease.

The study authors described how metabolic inflexibility may contribute to poor health. Insulin resistance occurs when the body’s metabolism of carbohydrates breaks down and becomes less efficient due to beta cell dysfunction. A healthy person has no issue switching between fat or carbs as a source of energy, but an unhealthy person may struggle with either or both.

A more recent medical review explored the topic of metabolic flexibility in more detail, explaining many factors that influence it. Gastrointestinal peptide release, natural hormone production and mitochondrial function were all listed as factors which can determine metabolic flexibility.

The second review is more interesting than the first, because it also outlines research-backed ways to improve metabolic flexibility. Lifestyle interventions are effective for countering metabolic inflexibility, according to the scientists.

Exercise (both aerobic and anaerobic), losing weight for obese patients, interruption of sedentary behavior like short walks during work, and supplementation of certain amino acids like l-carnitine are all suggested to improve metabolic flexibility based on research.

Basically, the standard healthy lifestyle recommendations most people are used to hearing seem to be the biggest factors in enhancing metabolic flexibility.

Lumen claims to measure carbon dioxide levels in the breath to determine a “flex score” that shows consumers how flexible their metabolism is. It’s important to note that neither medical review we examined mentioned carbon dioxide levels at all.

Questionable Health Claims

Lumen makes many health claims on their website that we find to be extremely questionable.

Lumen did publish a medical trial proving that their device can accurately measure whether carbs or fats are being used as a source of fuel, but there doesn’t appear to be any evidence that this information can help optimize metabolic flexibility beyond the basic recommendations we’ve already covered.

Why does it matter whether a person is burning fat or carbs for fuel if they’re healthy? The entire premise behind the company is confusing to us.

Lumen makes bold claims about the general health benefits of metabolic flexibility, but doesn’t explain at all how their device helps achieve that. Under a “How can we improve metabolic flexibility” header, Lumen gives generic advice like “Exercise” – that’s good advice, but no one needs an overpriced hardware device to do that.

Lumen also makes questionable claims about insulin sensitivity, such as claiming that “macronutrient manipulation” improves metabolic flexibility due to its effect on insulin. We find this to be an absurd general claim to make, because insulin sensitivity varies across a population.

There is zero evidence that healthy adults who exercise regularly and have no blood sugar issues benefit from manipulating macronutrient levels. Some people perform better on high-carb diets, and some perform better on low-carb diets.

Someone with no insulin sensitivity issues does not benefit from trying to improve insulin sensitivity; that’s basic logic. Someone with insulin sensitivity issues may benefit from restricting carbs, which can improve beta cell function, but the Lumen doesn’t measure insulin sensitivity so it seems useless for this population as well.

At a high level, the issue with this company is they provide information that doesn’t seem to be very useful for improving health. We can track all sorts of biometric data, but if that data doesn’t provide valuable insights it’s a waste of time and money. If the best way to improve metabolic flexibility is to maintain a healthy weight, exercise and reduce sedentary behavior, knowing the exact state of fuel metabolism doesn’t seem to add any value at all.

Given that there is no published medical proof that Lumen improves metabolism beyond standard health recommendations, we strongly disagree with the claims on their homepage of “enhanced” fat burning and weight loss. We find most of their claims to be lacking in any evidence, and believe it reflects poorly on the ethics of the company.

If a consumer buys a phone app that buzzes to tell them to go for a run, the phone app doesn’t “melt away fat,” the fact that they went for a run does. Lumen is the phone app in this analogy; a device that may suggest healthy practices, but doesn’t directly cause any physical changes, or provide recommendations that are proven to enhance fat loss beyond eating healthy and exercising.

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Lumen tracks data that we find to be totally useless for the purpose of weight loss or optimizing health. Healthy consumers see no proven benefit from changing lifestyle factors to change whether they burn fat or carbs as a primary energy source.

Unhealthy consumers suffering from metabolic disorder may benefit from carb restriction, but the state of their insulin sensitivity can already be measured with standard medical devices so we find no additional benefit from using the Lumen in this patient population.

The Lumen is a well-designed product with a sleek website that gives you pointless information. We strongly recommend avoiding it and saving your money.

If Lumen actually publishes medical studies in the future that prove their product enhances metabolic flexibility in the aggregate beyond standard health recommendations like eating healthy and exercising, we will consider changing our stance, but for now we don’t project that this device will provide any benefit to users.

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